To obtain water from a single source instead of separate hot and cold water taps, plumbing manufacturers have combined water sources downstream from separate taps, providing one spigot for outgoing, mixed water. Alternatively, one tap has been used to allow hotter or colder water to be discharged from a common outgoing pipe connected to two diverse temperature sources. In either of the above described systems, however, a user must let the water flow for some time while the resultant temperature of the water is adjusted. Moreover, the previously described systems offer no protection from sudden or sporadic hot or cold spurts. Thus each time any of the units has to be used, some amount of clean and fresh water is wasted. The present invention is intended to put an end to this wastage. It is thought to be more convenient than currently available systems and is economical to produce.